System and Method for Reducing Static Pressure in Air Handlers

ABSTRACT

A system and method for improving the efficiency of air handling units by reducing the static air pressure within units. The system and method utilizes rotary union mounts to fluidly connect the heating and cooling coils within the system. The rotary union mounts allow the heating and/or cooling coils to be rotated flush within the housing of the air handling unit when the coil(s) are not in use and thereby out of the air flow path. Rotating the coils out of the air flow path reduces the static air pressure within the air handling unit and significantly improves the efficiency of the system by reducing the horsepower requirement and power consumption of the system fan. The rotary union mounts allow the coil(s) to be selectably rotated out of the air flow path based on system demand requirements.

I. FIELD OF THE INVENTION

This invention relates generally to a system and method for improvingthe efficiency of air handling systems. More particularly, thisinvention relates to a system and method for improving the air flowwithin the ducts of air handling systems by significantly reducing thestatic pressure therein.

II. BACKGROUND OF THE INVENTION

Heating, Ventilation and Air Conditioning (HVAC) systems are used tocondition and control the air within enclosed spaces, such as officebuildings, mainframe rooms, and data centers (or server farms). Thesesystems heat, cool, and/or circulate the air within the space in orderto meet the environmental air requirements of the space. HVAC systemsutilize air handlers or air handling units (AHUs) to supply heating andcooling in the most efficient and cost effective manner possible.

Air handling units typically include cooling coils, heating coils,filters, and a fan or blower unit. The air handling units connect to theductwork of the HVAC system to supply the conditioned air throughout thespace. The system may also include humidifiers or dehumidifiers tocontrol the humidity level of the air. The cooling coils act to cool orreduce the temperature of the air within the ductwork. The heating coilsact to heat or increase the temperature of the air within the ductwork.The optional filter acts to remove excessive particulate matter from theair flow. Importantly, the filter and coils are typically disposed oversubstantially the entire internal cross-section of the ductwork in orderto help ensure that all of the air is conditioned.

FIG. 1 illustrates an exemplary known air handling unit 100. Airhandling unit 100 includes housing 110 that connects to the ductwork(not shown) the HVAC system. Inlet air flow 120 is pulled through theductwork and into housing 110 by fan or blower unit 150. Fan 150 alsopulls the air flow 120 through filter 130, cooling coil or element 140,and heating coil or element 150. The conditioned air flow 170 is thenforced into the space by fan 160. As the air flow 120 is pulled throughfilter 130 particulate matter is removed from the air flow stream. Theair flow 120 is then pulled through both cooling coil 140 and heatingcoil 150 by fan 160 in order to cool or heat the air before the air isforced back into circulation by fan 160.

In the known air handling system, both the cooling coil 140 and heatingcoil 150 remain fixed across the entire cross-section of the housing 110at all times. This is true even though only either the cooling coil(s)or heating coil(s) will be in operation at any given time, i.e., thecooling coil 140 and heating coil 150 do not operate simultaneously. Forexample, during times in which the cooling function of the air handlingunit 100 is in operation, only the cooling coil 140 is utilized tocondition (cool) the air flow 120. Similarly, during times in which theheating function of the air handling unit 100 is in operation, only theheating coil 150 is utilized to condition (heat) the air flow 130.

The static air pressure within the air handling unit is increased by thevarious components disposed within the system which provide resistanceto the air flow from the fan, such as the cooling coils, heating coils,filters, ductwork, etc. A significant power user in air handling unitsis the fan motor which must develop enough energy to overcome the staticair pressure created by the various components in the air flow path. Anyreduction in the static air pressure within the air flow path willprovide significant savings in fan motor horsepower and powerconsumption of the unit.

The filter 130, cooling coil 140 and heating coil 150 all increase thestatic air pressure within housing 110. The increased static airpressure diminishes the efficiency of the fan 160 and requires the fanto work harder to move the air flow 120 through the housing and theconditioned air flow 170 into the space. Removing the unutilized(additional) cooling or heating coil(s) from the cross-section of thehousing 110 when the coil(s) are not in use would significantly improvethe efficiency of the air handling unit 100.

III. SUMMARY OF THE INVENTION

This invention in at least one embodiment provides an apparatus forallowing air to flow through the HVAC unit without having to flowthrough unnecessary heating or cooling coils, thus reducing fan energyrequired due to pressure drop across the coils.

This invention in at least one embodiment provides a method for reducingthe static pressure losses associated with the heating and cooling coilsin an HVAC system

IV. BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is described with reference to the accompanyingdrawings, wherein:

FIG. 1 illustrates an example of a known Air Handling Unit (AHU).

FIG. 2A illustrates an embodiment of the Air Handling Unit (AHU) of thepresent invention.

FIG. 2B illustrates an alternative view of a coil of the Air HandlingUnit (AHU) of the present invention.

FIG. 2C illustrates an alternative view of a heating of the Air HandlingUnit (AHU) of the present invention.

FIG. 3 illustrates an embodiment of the Air Handling Unit (AHU) of thepresent invention in cooling mode.

FIG. 4 illustrates an embodiment of the Air Handling Unit (AHU) of thepresent invention in heating mode.

FIGS. 5A-5C illustrate a method of converting the Air Handling Unit(AHU) of the present invention to cooling mode.

FIGS. 6A-6C illustrate a method of converting the Air Handling Unit(AHU) of the present invention to heating mode.

Given the following enabling description of the drawings, the inventionshould become evident to a person of ordinary skill in the art.

V. DETAILED DESCRIPTION OF THE DRAWINGS

The present invention in at least one exemplary embodiment provides asystem and method that reduces the static air pressure within airhandling systems. The present invention includes flexibly configurablecomponents that allow for a more efficient system layout based oncurrent user needs. FIG. 2A illustrates an embodiment of the airhandling unit 200 of the present invention. Air handling unit 200includes air handling unit housing 210, optional filter 230, coolingcoil or element 240, rotary unions 245, heating coil or element 250,rotary unions 255, and fan or blower unit 260. Fan 270 pulls inlet airflow 220 through the ductwork (not shown) of the HVAC system and intohousing 210. Air flow 220 passes through the optional filter 230 inorder to remove excessive particulate matter from the air. The air flow220 is then pulled through cooling coil 240 and/or heating coil 250 byfan 260 to cool or heat the air. The conditioned, i.e., heated orcooled, air flow 270 is then forced into circulation by fan 260.

FIG. 2B-2C, respectively, illustrate front views of examples of thecooling coil 240 and heating coil 250 of the air handling unit 200 ofpresent invention. As illustrated in FIG. 2B, rotary unions 245 areattached to both (inlet and outlet) sides of cooling coil 240 to mountand provide a rotatable attachment of cooling coil 240 to housing 210.Similarly, as illustrated in FIG. 2C, rotary unions 255 are alsoattached to both sides of heating coil 250 to mount provide a rotatableattachment of heating coil 250 to housing 210. The rotary unions 245,255 provide fluidic coupling of the coils 240, 250 while allowing thecoils 240, 250 to be selectably rotated out of the fluid flow pathwithin the housing 210. Rotary unions 245, 255 may be mounted on anywall of the housing 210, e.g., top wall, bottom wall, or either sidewall.

Rotary unions 245 allow the cooling coil 240 to be rotated to a positionthat is flush or flat adjacent the wall of housing 210 and out of thepath of air flow 220 when the cooling coil 240 is not in use, i.e., thecooling function is “OFF” or the heating function is “ON”. Similarly,rotary unions 255 allow the heating coil 250 to be rotated flat againsthousing 210 and out of the path of air flow 220 when the heating coil250 is not in use, i.e., the heating function is “OFF” or the coolingfunction is “ON”. The coils 240, 250, including rotary unions 245, 255,may be rotated by various actuation means, e.g., cable-pulley,rack-pinion, pistons, and the like, based on system demand requirements.The actuation means may be manually controlled, e.g. through an accesspanel, or automatically controlled, e.g., by a programmable computer.The system may also include, for example, a latch to attach the coils240, 250 to the housing 210.

FIG. 3 illustrates an embodiment of the air handling unit 300 of thepresent invention in cooling mode. Air handling unit 300 includesoptional filter 330, cooling coil 340, rotary unions 345, heating coil350, rotary unions 355 and fan 360. In cooling mode, the heating coil350, which is not being used, is rotated to a position flat againsthousing 310 and out of the path of air flow 320. This arrangementreduces the static pressure within housing 310 and improves theefficiency of fan 360. The conditioned air flow 370 is forced intocirculation by the fan 360.

FIG. 4 illustrates an embodiment of the air handling unit 400 of thepresent invention in heating mode. Air handling unit 400 includesoptional filter 430, heating coil 440, rotary unions 445, heating coil450, rotary unions 455 and fan 460. In heating mode, the cooling coil440 is rotated to a position flush with housing 410 and out of the pathof air flow 420. This arrangement reduces the static pressure withinhousing 410 and improves the efficiency of fan 460. The conditioned airflow 470 is forced into circulation by the fan 460.

FIGS. 5A-5C illustrate a method of converting the air handling unit 500of the present invention to cooling mode. The method of converting theair handling unit 500 of the present invention to cooling mode begins atFIG. 5A with the air handling unit 500 in dual mode. The air handlingunit 500 includes optional filter 530, cooling coil 540, rotary unions545, heating coil 550, rotary unions 555, and fan 560. In dual mode boththe cooling coil 540 and heating coil 550 are perpendicularly deployedover substantially the entire internal cross-section of the housing 510such that the air flow passes through both the cooling coil 540 andheating coil 550 en route to fan 560. At FIG. 5B, the heating coil 550is rotated about the rotary unions 555 toward the housing 510. At FIG.5C, the heating coil 550 is rotated about rotary unions 555 to aposition flat against housing 510 such that inlet air flow 520 issubstantially unobstructed by the heating coil 550 as the air flowtravels towards fan 560. The air handling unit 500 is now in coolingmode and the static air pressure within the air handling unit 550 issubstantially reduced compared to the static air pressure within the airhandling unit 500 in dual mode as shown, for example, in FIG. 5A.Therefore, fan 560 can more efficiently cycle the inlet air flow 560 andconditioned air flow 570 through the air handling unit 500.

FIGS. 6A-6C illustrate a method of converting the air handling unit 600of the present invention to heating mode. The method of converting theair handling unit 600 of the present invention to heating mode begins atFIG. 6A with the air handling unit 600 in dual mode (heating andcooling). The air handling unit 600 includes optional filter 630,cooling coil 640, rotary unions 645, heating coil 650, rotary unions655, and fan 660. In dual mode both the cooling coil 640 and heatingcoil 650 are perpendicularly deployed over substantially the entireinternal cross-section of the housing 610 such that the air flow passesthrough both the cooling coil 640 and heating coil 650 en route to fan660. At FIG. 6B, the cooling coil 640 is rotated about the rotary unions645 toward the housing 610. At FIG. 6C, the cooling coil 640 is rotatedabout rotary unions 645 to a position flat against housing 610 such thatinlet air flow 620 is substantially unobstructed by the cooling coil 640as the air flow travels towards fan 660. The air handling unit 600 isnow in heating mode and the static air pressure within the air handlingunit 600 is substantially reduced compared to the static air pressurewithin the air handling unit 650 in dual mode as shown, for example, inFIG. 6A. Therefore, fan 660 can more efficiently cycle the inlet airflow 660 and conditioned air flow 670 through the air handling unit 600.

As used above “substantially”, “generally”, “relatively” and other wordsof degree are relative modifiers intended to indicate permissiblevariation from the characteristic so modified. It is not intended to belimited to the absolute value or characteristic which it modifies butrather possessing more of the physical or functional character than itsopposite, and preferably, approaching or approximating such a physicalor functional characteristic.

The exemplary embodiments described above may be combined in a varietyof ways with each other. Furthermore, the steps and number of thevarious steps illustrated in the figures may be adjusted from thatshown.

It should be noted that the present invention may, however, be embodiedin many different forms and should not be construed as limited to theembodiments set forth herein; rather, the embodiments set forth hereinare provided so that the disclosure will be thorough and complete, andwill fully convey the scope of the invention to those skilled in theart. The accompanying drawings illustrate exemplary embodiments of theinvention.

Although the present invention has been described in terms of particularexemplary embodiments, it is not limited to those embodiments.Alternative embodiments, examples, and modifications which would stillbe encompassed by the invention may be made by those skilled in the art,particularly in light of the foregoing teachings.

Those skilled in the art will appreciate that various adaptations andmodifications of the exemplary embodiments described above can beconfigured without departing from the scope and spirit of the invention.Therefore, it is to be understood that, within the scope of the appendedclaims, the invention may be practiced other than as specificallydescribed herein.

1. A system comprising: a housing; a cooling coil disposed within saidhousing; at least a first rotary union in fluid communication with saidcooling element and mounted to the inside of said housing; a heatingcoil disposed within said housing; at least a second rotary union influid communication with said heating element and mounted to the insideof said housing; and a fan disposed within said housing.
 2. The systemaccording to claim 1, wherein said cooling coil is rotatably connectedto said first rotary union mount.
 3. The system according to claim 2,wherein said cooling coil is capable of rotating about said first rotaryunion mount to a position substantially flush with said housing.
 4. Thesystem according to claim 1, wherein said heating coil is rotatablyconnected to said second rotary union mount.
 5. The system according toclaim 4, wherein said heating coil is capable of rotating about saidsecond rotary union mount to a position substantially flush with saidhousing.
 6. The system according to claim 1, wherein said cooling coilis capable of rotating about said first rotary union mount to a positionsubstantially flush with said housing and said heating coil is capableof rotating about said second rotary union mount to a positionsubstantially flush with said housing.
 7. The system according to claim1, wherein said cooling coil includes a fluid inlet and a fluid outlet.8. The system according to claim 1, wherein said heating coil includes afluid inlet and a fluid outlet.
 9. A system according to claim 1,wherein said cooling coil is placed upstream from said heating coil. 10.A system according to claim 1, wherein said heating coil is placedupstream from said cooling coil.
 11. A system according to claim 1,further comprising a filter disposed within said housing.
 12. A systemaccording to claim 1, further comprising: a first ductwork attached toan inlet side of said housing, and a second ductwork attached to anoutlet side of said housing.
 13. A system comprising: a housing; acooling element disposed across substantially the entire interiorcross-section of said housing; at least a first rotary union mountattached to said cooling element and said housing; a heating elementdisposed across substantially the entire interior cross-section of saidhousing; and at least a second rotary union mount attached to saidheating element.
 14. The system according to claim 13, furthercomprising a fan disposed within said housing.
 15. The system accordingto claim 13, wherein said cooling element is rotatably connected to saidfirst rotary union mount and is capable of rotating about said firstrotary union mount to a position substantially flush with said housing.16. The system according to claim 13, wherein said heating element isrotatably connected to said second rotary union mount and is capable ofrotating about said second rotary union mount to a positionsubstantially flush with said housing.
 17. A method comprising:providing a housing; disposing a cooling coil within said housing;providing at least a first rotary union mount in fluid communicationwith said cooling element; disposing a heating coil within said housing;providing at least a second rotary union mount in fluid communicationwith said heating element; and disposing a fan within said housing. 18.The method according to claim 17, further comprising: rotating saidcooling coil about to a position substantially flush with said housing.19. The method according to claim 17, further comprising: rotating saidheating coil about to a position substantially flush with said housing.20. A system according to claim 17, further comprising: attaching afirst ductwork to an inlet side of said housing, and attaching a secondductwork to an outlet side of said housing.